Plate production system with low level bundling, stacking, and transport

ABSTRACT

A composite plate production system having at a welding station a combined pressure-assembler, welding clamp, and precision stacker ram-carriage unit, feeding a low-level self loading and unloading shuttle by means of a stacking table located above the shuttle, the shuttle being arranged for conveying and off-loading bundles onto a transfer table having a pivotal edge-angle for stabilizing bundles rotated during hoist pick-up in preparation for edge-down bundle storage.

United States Patent Quintilian Apr. 2, 1974 [54] PLATE PRODUCTIONSYSTEM WITH LOW 3,646,657 3 1972 Small 29/200 A LEVEL BUNDLING,STACKING, AND 3,729,798 5/1973 Ejlertsen 29/200 A 3,707,257 12/1972Wogerbauer et al. 228/6 TRANSPORT 2,506,550 5/1950 Morrison 29/200 A[75] Inventor: Bartholomew Frank Quintilian, 3,709,423 1/1973 Hano etal. 228/6 Baltimore, Md.

Primary Examiner-Richard J. l-lerbst [73] Assignee. lrgippers Company,Inc., Pittsburgh, Assistant Examiner James R. Duzan Attorney, Agent, orFirm-Boyce C. Dent; Oscar B. [22] Filed: Dec. 13, 1972 Brumback; Olin E.Williams [21] Appl. No.: 314,712 [57] ABSTRACT 52 us. Cl 29/464, 29/33R, 29/453 A composite Plate Production system having at a 51 int. ClB23q 3/00 Welding Station a combined pressure-assembler, Weld- [58]Field of Search 219/86, 87, 107; 228/6, ing clamp, and Precision Slackerram-carriage unit, 223/470 29/33, 453, 200 R, 200 A 208 feeding alow-level self loading and unloading shuttle R 464, 33 R, 33 p by meansof a stacking table located above the shuttle,

the shuttle being arranged for conveying and off- 5 References Citedloading bundles onto a transfer table having a pivotal UNITED STATESPATENTS edge-angle for stabilizing bundles rotated during hoist 3 708100 1/1973 Buchfuher at al 228/47 pick-up in preparation for edge-downbundle storage. 3,557,439 1/1971 Dykeman 29/200 A 11 Claims, 4 DrawingFigures PATENTEDAPR 2:914 3300.404

SHEET 1 or 3 FIG. I

PATENTEUAPR 2 @914 SHEU 2 0F 3 m OE PATENTEDAPR 2:914

3; SHiEI 3 0F 3 800 404 FIG.3

PLATE PRODUCTION SYSTEM WITH LOW LEVEL BUNDLING, STACKING, AND TRANSPORTCROSS REFERENCES TO RELATED APPLICATION BACKGROUND OF THE INVENTIONDESCRIPTION OF THE PRIOR ART Collecting electrodes or precipitatorplates of the types assembled from roll formed, cut to length mod- .ulesare disclosed in US. Pat. No. 3,418,792, issued on December 31, 1968, toBartholomew F. Quintilian and Robert .I. W. Williams, and entitledModular Collector Electrode for Electrostatic Precipitators Suchprecipitator plates have heretofore been assembled by interlocking thejoints serially at one station, welding the hempieces across the ends ata second station, individually transferring the assembled precipitatorplates by lifting hoist to a bundling and turnover fixture at a thirdstation, and transferring the up-ended bundles of plates by a heavycrane to shipping or other storage areas.

This old-art sequence causes back-ups from the output end which at timeslimit the roll-forming operation to substantially less than ratedcapacity. When the heavy or plant-wide crane normally used for movingthe bundles shifts temporarily to another job, production stops. Whilethe heavy crane is being coupled to the top of an up-ended bundle on thebundling and turnover fixture (a process done slowly to protect theworkman engaging the hook at considerable height above the floor)production stops at the welding station. While stacks of plates on thebundling and turnover fixture are being squared for bundling and arebeing united into bundles, if any difficulty arises requiringappreciable time tocorrect, production stops up stream at the weldingstation. While the hoist operator engages the last plate assembled withthe suction cups of the auxiliary hoist normally used for lifting theindividual plates, and slowly and carefully lifts it from and clears itpast the welding fixture, production stops at the welding station. Eachtime production stops at the welding station, production stops up theline at the press and the roll former and cut-off, idling workers aswell as equipment. I

Other obstacles and difficulties encountered in practice of the old artmethod described include plate warpage caused by cumulative errorinduced by serial pressure-interlocking of the successive modules, anddifficulty in correcting such warpage after the endpieces are welded inplace.

The cross referenced co-pending application describes one solution tothe above problems in the-form of means and methodrequiring time andcapital investment which are'modest in terms of the resultant increasesin production andproduct quality and the decreases in worker fatiguehazard and loss through damage.

The present invention discloses a system which solves the problem of theold-art obstacles in production of precipitator plates and the like in amanner considerably more efiicient than any previously proposed, whichis adapted to produce closer-tolerance products than previous systems,and which is safe and convenient by design, but which requires asomewhat greater capital investment than the system disclosed in theco-pending application.

SUMMARY OF THE INVENTION A first object of the present invention is toprovide precipitator plate production means and method which reduce thenumber of product manipulations required in the pressure-assembling,welding and stacking operations, insuring better contour and alignmentin these crucial stages while greatly increasing sureness and speed ofhandling;

another object of the present invention is to provide means and methodas described which include means for increasing speed and the safety ofbundle up-ending for storage;

futher objects of the invention are to provide a system as describedwhich is straightforward, simple, dutable, and economical in operation.

In representative embodiment the invention includes a composite plateproduction system having associated with a welding station an integratedpressureassembler, welding aligner, and stacker, and apositivepositioning transfer system.

The above and further objects and novel features of the invention willappear more fully from the following detailed description when the sameis read in connection with the accompanying drawings. It is to beexpressly understood, however, that the drawings are not intended as adefinition of the invention but are for the purpose of illustrationonly.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings, wherein like partsare marked alike;

FIG. 1 is a diagrammatical plan view of a production system according tothis invention, partially broken away to show details below.

FIG. 2 is an elevation viewed generally from 2-2, FIG. 1;

FIG. 3 is a diagrammatical elevation of a bundle transfer frame; and

FIG. 4 is an isometric view of a pressure-interlocking array of modulesof a type previously invented and representative of a stage ofproduction in the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. 1 and 2 show, indiagrammatical form, details of a preferred embodiment 10 of thisinvention.

Roll forming machine 12 produces and serially ejects cut-to-lengthpanel-like modules 14 having interlockable edges l6, 18. A run-out table20 is disposed at right angles to the roll forming machine, and themodules are moved along the table by conveyor belts or other suitablemeans.

The modules are arranged in groups with successive modules facingalternately up and down and then are loosely assembled in arrays 22 byoverlapping the interlockable edges. The arrays of modules are thenpassed to a fabrication and transfer station 24 where the overlappededges are pressure-interlocked by a reciprocable unit, are completed bythe welding of a split-tube type, hempiece 26, 28 across each end, andare conveyed to a bundle transfer frame 30 by a combinationpress/welding-clamp/stacker unit 32.

In FIG. 1, combination press/welding-clamp/stacker unit 32 is shownpartially roken away to reveal details below, but comprises generallythe following described elements, shown at completion of a precipitatorplate 34 and before removal of the plate to a stack. Most of theseelements can be seen in FIG. 2.

Press table 36 uniformly supports the precipitator plate 34 frombeneath. Stanchions 38 support overhead conveyor tracks 40 and 40'parallel with and to the sides of the run-out table and press table, andover the bundle transfer frame 30 at the end of the press table.

Ram carriage 42 has rollers 44 movably mounting it to the overheadtracks 40, 40. The ram carriage is shown in the press/clamp positionabove the press table. Hydraulic rams 46, which are synchronized byhaving a common pressure feed represented by source 46a and reversingvalve 46b, depend from the ram carriage in spaced rows adapting clampingblades 48 on the ends of the rams to exert interlocking pressuredirectly on each joint 50 of the overlapping edges of the work below,when the rams extend. After the joints snap together, the rams maintainpressure on the work, keeping it clamped in flat alignment against theplanar press table surface in preparation for welding. At the same time,grippers 52 are energized. The grippers may be magnetic or suction, andof any conventional design. These are fixed to the ram assembly abovethe work in a manner described later. The grippers remove buckles in theflat areas 54 of the modular array, further aligning it for welding.Finally the hempieces 26 and 28 are attached by resistance welders 56and 58 (FIG. 1) which are disposed at the sides of the press table 36.The welders are suitably provided with means for travelling from spot tospot along the hempieces during the fastening process, as by beingmounted slidably on rails 60 and 62, and are supplied with current fromtransformers 64 and 66, respectively, in any conventional manneradapting the welders to advance to the work and to retract to thepositions shown, as for example by flexible cables 65 and 67.

After the hempieces are welded on, the ram clamping pressure is releasedbut through continued energization, the grippers 52 are caused tocontinue to hold the finished precipitator plate 34, in preparation forlifting and attaching. Any conventional circuit represented by box 52aand the associated line 52b can be used for operation of the grippers inthe synchronism required.

Next the rams 46 are retracted, in unison, lifting the precipitatorplate 34, and the ram carriage motor 53 is activated, moving theprecipitator plate to a predetermined position over the bundle transferframe 30 in position for lowering it onto the frame and successivelystacking other precipitator plates on it as they are completed. Thebundle transfer frame 30 is essentially a table longitudinally dividedinto spaced-apart halves 68 and 70.

Bundle rod attachment bars 72 affixed on the upper surface 74 of thebundle transfer frame 30 serve to support bolt-like bundle rods 76detachably in an upright position in holes 72a. Each bundle rod has anut threaded on the bottom leaving a lower portion of the rod exposedbelow the nut to slip into hole 72a. Openings 78 in the precipitatorplates engage the bundle rods as the plates are lowered by extension ofthe rams 46 during stacking.

When the stacks are complete, fasteners such as nuts 80 are secured onthe tops of the bundle rods, uniting the stacks as bundles.

A shuttle car 82 arranged to pass beneath the bundle transfer frame 30on tracks 84, self-loads the bundle by elevating spreaders 112 throughopenings 86 provided in the bundle transfer frame, and conveys thebundle to a storage area where it off-loads the bundle by lowering itonto a second transfer frame generally like the first. The bundle 104 isthen picked up by crane and deposited edge-down in storage, as at 104,FIG. 2.

FIG. 2 additionally shows other details of the run-out table 20, thepress/welding-clamp/stacker unit 32, and the bundle transfer frame 30and shuttle car 82 arrangement. The surface 88 of the press table 36 ispreferably continuous with the surface 90 of the run-out table 20. Thepress table surface preferably has local supports 91 under the positionsof greatest load, with the local supports resting on a massive sill 92,but may be of any equivalent construction providing a suitably flat,rigid, and strong surface for working precipitator plates 34.

The stanchions 38 at the corners of the press table unite the sill 92and the overhead conveyor tracks 40 into a strong, rigid box-like frame.The conveyor tracks are heavy channels containing the rollers 44 of theram carriage, top and bottom. Shim plates 94 are fixed to the upper legsof the channel shape in position over the press table to reduce backlashunder thrust of the rams.

The rams 46 are preferably pivotally suspended by stub axles 96 fromheader flange 98 longitudinally fixed to the ram carriage. Each rampiston 100 has one of the clamping blades 48 fixed at the free end ofthe piston; the blades are suitably spaced for engaging the joints ofthe precipitator plates. The ram pistons pass through and are welded toor clamped in an aligning pistonheader-plate 102 which also mounts theplate grippers 52 between and in spaced relation to the pistons. Thegrippers are mounted in-plane and, as noted, apply aligning pressure(upward or downward as needed, by means of the fixed relation and thegripping capability) to the flat areas 54, of the modules during thewelding operation.

As indicated by the arrows, on retraction of the rams, the grippers 52lift the just-completed precipitator plate, the ram carriage is thenactuated, moves to the stacking position, and extends the rams, loweringthe precipitator plate over the guiding and securing bundle rods 76, andnesting it in the stack.

Pressure-nesting may be employed, as when the stack is complete and nuts80 are to be applied to secure it as a bundle 104. Following thestacking movement, the grippers are released and the ram carriageretracts and returns to the press table position.

Because high rates of carriage travel can be precisely controlled byconventional means symbolized by limit switch 106 and stop 107, transferand stacking of the completed work according to the present inventionrequires little more time, if any, than that necessary to position thesucceeding array of modules on the press table.

As shown also in FIG. 2, the bundle transfer frame halves 68 and 70overhang the sides of the shuttle car 82. The shuttle car jacks arepreferably paired as at 108 and 110, with each pair supporting atransverse spreader 112.

FIG. 3 is an end elevation showing a bundle transfer frame 330 havingspecial provisions for upending and pickup of bundles by a crane 343after the bundles are off-loaded onto the bundle transfer frame by ashuttle car on reversal of the loading procedure.

Bundle transfer frame 330 is similar in construction to bundle transferframe 30 which was described in reference to FIGS. 1 and 2. However, toprevent bundle skidding during up-ending, a bundle-stabilizing angle 331having perpendicular legs 333 and 335 is pivoted at the apex by hingepin 337 along one side of the bundle transfer frame.

The shuttle car in offloading lowers the bundle 104 onto leg 333 whichhas been oriented in the horizontal, inwardturned direction. A thicknesscompensating strip 341 affixed along the other side of the bundletransfer plate levels the bundle.

The hookof crane 343 then engages at C, any conventional pickup fixture345 which is attached to the off-edge 347 of the bundle by the bundlerods or in any other conventional manner. The hook then simultaneouslylifts and advances from right to left in the Fig ure, passing throughintermediate positions such as C in which the near edge 349 of thebundle would skid off the table if not restrained. After the bundle isupanddown at C it is lifted free, transported, and deposited edge downin storage.

Damage caused by scuffing, bumping, and bending is avoided by thecorner-protecting fit and the rotation feature of angle 331. The hook issafely engageable at a low level, and danger to personnel in theremainder of the up-ending operation is minimized. Any desired number oftransfer frames of this type can be used to optimize crane usage.

FIG. 4 is an isometric view of a prior invention array of edgeinterlockable rectangular modules 14 of the general type the presentsystem is adapted to produce and process. The pressure interlockablefeatures is shown at A, a locked joint, and at B a loosely overlappedjoint in position for pressure interlocking.

Having thus described the invention in its best embodiment and mode ofoperation, what is described to be claimed by letters patent is:

1. In a method of assembling and staging for shipment a plurality ofprecipitator plates or the like, each precipitator plate being anassembly of a plurality of edge-overlapped pressure interlocked modulesand a first and second hempiece respectively extending across the firstand second ends of the precipitator plate, the improvement comprisingthe steps:

a. overlapping the edges of a plurality of said modules;

b. simultaneously applying pressure to and interlocking all overlappingedges of the plurality of modules;

c. maintaining the pressure on the modules and gripping and aligningportions of the modules intermediate the overlapping edges;

d. fastening first and second hempieces respectively across the firstand second ends of the plurality of interlocked modules, therebycompleting assembly of a precipitator plate;

e. releasing the interlocking pressure and by means of said grippinglifting the pecipitator plate;

f. conveying the precipitator plate horizontally to a stacking location;

g. lowering the precipitator plate to a predetermined level;

h. releasing the gripping, supporting the precipitator plate from belowat the level to which lowered;

i. repeating steps (a) through (g), resting each successive precipitatorplate on the prior assembled precipitator plate, thereby forming abundle of precipitator plates;

j. liftingly engaging the bundle of precipitator plates from a positionbelow the bundle of precipitator plates;

k. horizontally moving the bundle of precipitator plates to an area awayfrom said stacking location; and

l. offloading the bundle of precipitator plates in said area, therebyassembling and staging for shipment a plurality of precipitator plates.

2. In a method as recited in claim 1, the additional improvementcomprising:

in step (g) guiding the precipitator plate during lowering to the levelby reference to at least one position at the level; and

in step (i) maintaining the guiding and fastening the bundle together byreference to the guiding.

3. In a method as recited in claim 2, the additional improvementcomprising:

in step (I) pivoting the offloaded bundle of precipitator plates aboutone corner thereof to a vertical position, and depositing the bundle ofprecipitator plates on edge. 4. In a system for assembling and stagingfor shipment a plurality of plates, each plate comprising a plurality ofmodules in edge-interlocked array with first and second end-pieces fixedacross the respective first and second ends of the array, theimprovement comprising:

unitary movable means including:

means extensible for applying pressure to and simultaneouslyinterlocking all overlapping edges of an edge-overlapped array ofmodules, includmg means energizable for gripping a portion of the arrayof modules other than the overlapped edges concurrently with saidapplication of pressure, thereby aligning said portion of the array forthe attachment of hempieces and the like to form a plate;

means for retracting the extensible means and causing the energizablemeans to lift a said plate;

means for conveying said gripped plate for stacking by the extensiblemeans and the energizable means;

means for lowering a said plate conveyed for stacking, including meansfor re-extending the extensible means and means for de-energizing theenergizable means;

means cooperative with the unitary movable means, for receiving andaligning the plate for stacking including means for uniting a pluralityof stacked plates as a bundle;

means for raising said bundle from the receiving means and fortransporting the bundle away from the receiving means;

means for offloading a said bundle from the raising and transportingmeans, and

means for rotating a said bundle and depositing in on-edge for storage.

5. In a system as recited in claim 4, wherein the system includes atable, wherein the means extensible includes:

a vertically reciprocable ram system positionable over the table;

a plurality of laterally spaced clamping blades responsively attached tothe ram system;

a plurality of plate grippers comprising said means energizable, saidplurality of plate grippers attached to the to the ram system in spacedrelation to the clamping blades;

and wherein the means for conveying includes a carriage arranged formoving the ram system to a stacking location.

6. In a system as recited in claim 5, and additionally means forattachment of hempieces to modular arrays, comprising:

first and second ways parallel with and respectively positioned at firstand second sides of the table;

a movable mounting on each way;

and a fastener supported by each movable mounting,

thereby adapting the fasteners for movement parallel with said sides ofthe table.

7. In a system as recited in claim 5, the means for receiving andaligning plates comprising:

a base;

a plurality of holders proximate the base, and

a plurality of vertically elongate members removably held by saidholders in position for engaging plates during stacking.

8. In a system as recited in claim 7, the means for uniting stackedplates as a bundle comprising at least one member adapted for securingthe upper end of one of said vertically elongate members.

9. In a system as recited in claim 7, the means for raising from belowand transporting a bundle away from the receiving means comprising:

a shuttle car, and

a jacking system on the shuttle car arranged for raising and lowering asaid bundle.

10. In a system as recited in claim 9, the means for offloadingcomprising:

a transfer frame having an opening arranged for receiving said shuttlecar and having a surface at a level to receive a bundle lowered by saidshuttle car jacking system.

11. In a system as recited in claim 10, the means for rotating anddepositing a said bundle on edge including:

a stabilizer having a pair of legs fixed at an angle to each other;

a pivot securing the stabilizer to the transfer frame in position forreceiving in the angle between the legs thereof a comer of a bundlelowered by the shuttle car;

and a hoist movably arranged above the transfer frame in position forrotating to a vertical position a bundle having a corner stabilized insaid angle and for depositing a said bundle for storage in an edge ofthe bundle.

1. In a method of assembling and staging for shipment a plurality ofprecipitator plates or the like, each precipitator plate being anassembly of a plurality of edge-overlapped pressure interlocked modulesand a first and second hempiece respectively extending across the firstand second ends of the precipitator plate, the improvement comprisingthe steps: a. overlapping the edges of a plurality of said modules; b.simultaneously applying pressure to and interlocking all overlappingedges of the plurality of modules; c. maintaining the pressure on themodules and gripping and aligning portions of the modules intermediatethe overlapping edges; d. fastening first and second hempiecesrespectively across the first and second ends of the plurality ofinterlocked modules, thereby completing assembly of a precipitatorplate; e. releasing the interlocking pressure and by means of saidgripping lifting the pecipitator plate; f. conveying the precipitatorplate horizontally to a stacking location; g. lowering the precipitatorplate to a predetermined level; h. releasing the gripping, supportingthe precipitator plate from below at the level to which lowered; i.repeating steps (a) through (g), resting each successive precipitatorplate on the prior assembled precipitator plate, thereby forming abundle of precipitator plates; j. liftingly engaging the bundle ofprecipitator plates from a position below the bundle of precipitatorplates; k. horizontally moving the bundle of precipitator plates to anarea away from said stacking location; and l. offloading the bundle ofprecipitator plates in said area, thereby assembling and staging forshipment a plurality of precipitator plates.
 2. In a method as recitedin claim 1, the additional improvement comprising: in step (g) guidingthe precipitator plate during lowering to the level by reference to atleast one position at the level; and in step (i) maintaining the guidingand fastening the bundle together by reference to the guiding.
 3. In amethod as recited in claim 2, the additional improvement comprising: instep (l) pivoting the offloaded bundle of precipitator plates about onecorner thereof to a vertical position, and depositing the bundle ofprecipitator plates on edge.
 4. In a system for assembling and stagingfor shipment a plurality of plates, each plate comprising a plurality ofmodules in edge-interlocked array with first and second end-pieces fixedacross the respective first and second ends of the array, theimprovement comprising: unitary movable means including: meansextensible for applying pressure to and simultaneously interlocking alloverlapping edges of an edge-overlapped array of modules, includingmeans energizable for gripping a portion of the array of modules otherthan the overlapped edges concurrently with said application ofpressure, thereby aligning said portion of the array for the attachmentof hempieces and the like to form a plate; means for retracting theextensible means and causing the energizable means to lift a said plate;means for conveying said gripped plate for stacking by the extensiblemeans and the energizable means; means for lowering a said plateconveyed for stackiNg, including means for re-extending the extensiblemeans and means for de-energizing the energizable means; meanscooperative with the unitary movable means, for receiving and aligningthe plate for stacking including means for uniting a plurality ofstacked plates as a bundle; means for raising said bundle from thereceiving means and for transporting the bundle away from the receivingmeans; means for offloading a said bundle from the raising andtransporting means, and means for rotating a said bundle and depositingin on-edge for storage.
 5. In a system as recited in claim 4, whereinthe system includes a table, wherein the means extensible includes: avertically reciprocable ram system positionable over the table; aplurality of laterally spaced clamping blades responsively attached tothe ram system; a plurality of plate grippers comprising said meansenergizable, said plurality of plate grippers attached to the to the ramsystem in spaced relation to the clamping blades; and wherein the meansfor conveying includes a carriage arranged for moving the ram system toa stacking location.
 6. In a system as recited in claim 5, andadditionally means for attachment of hempieces to modular arrays,comprising: first and second ways parallel with and respectivelypositioned at first and second sides of the table; a movable mounting oneach way; and a fastener supported by each movable mounting, therebyadapting the fasteners for movement parallel with said sides of thetable.
 7. In a system as recited in claim 5, the means for receiving andaligning plates comprising: a base; a plurality of holders proximate thebase, and a plurality of vertically elongate members removably held bysaid holders in position for engaging plates during stacking.
 8. In asystem as recited in claim 7, the means for uniting stacked plates as abundle comprising at least one member adapted for securing the upper endof one of said vertically elongate members.
 9. In a system as recited inclaim 7, the means for raising from below and transporting a bundle awayfrom the receiving means comprising: a shuttle car, and a jacking systemon the shuttle car arranged for raising and lowering a said bundle. 10.In a system as recited in claim 9, the means for offloading comprising:a transfer frame having an opening arranged for receiving said shuttlecar and having a surface at a level to receive a bundle lowered by saidshuttle car jacking system.
 11. In a system as recited in claim 10, themeans for rotating and depositing a said bundle on edge including: astabilizer having a pair of legs fixed at an angle to each other; apivot securing the stabilizer to the transfer frame in position forreceiving in the angle between the legs thereof a corner of a bundlelowered by the shuttle car; and a hoist movably arranged above thetransfer frame in position for rotating to a vertical position a bundlehaving a corner stabilized in said angle and for depositing a saidbundle for storage in an edge of the bundle.